The current heat record for the month of September is 29.1 degrees and was measured in Stehag in Skåne on September 1, 1975. Tomorrow, exactly 44 years later, the record can be beaten.

- All the highest temperatures tend to be at the beginning of the month and we could have a new record tomorrow. In our forecasts, it is warmest in southeast Sweden, which means eastern Svealand, eastern Götaland and Gotland, says Deana Bajic.

May be record-breaking

In Sörmland, Östergötland, Kalmar and in Gotland temperatures are expected to be around 27-28 degrees. It will be sunnyest on Gotland, but according to SMHI's forecast, 30 degrees is expected in Norrköping.

- It's no wonder if we get higher than 29.1 degrees.

But while the warm summer air remains over southeastern Sweden, northwest Götaland has to prepare for autumnal rain and debris.

- Further west, a rainy area passes. There is a risk of heavy rainfall with thunderstorms in a large area - from northwest Götaland, large parts of Svealand and southwestern Norrland.

Risk of flooding

It is a cold front that passes with cooler air behind it and warm air in front. The large temperature differences between the air masses mean that thunderstorms and bursts are expected to be severe.

SMHI has also flagged the risk of large rainfall in several counties. It is about Gävleborg's inland, Jämtland, Västra Götaland, Dalarna, Värmland, Örebro, Västmanland, Södermanland, Östergötland and Jönköping.

- Locally, there may be flooding in connection with the rainfall coming in, as the soil does not have time to absorb all the water, says Deana Bajic.

In the evening, the summer weather is ending even in the eastern parts of the country.

- There the rain will come later in the afternoon and evening. Then the warm air is gone and it gets cooler.